5 supplements you’re probably wasting money on, and what actually works

Supplements are a multibillion-dollar business. Unfortunately, that also means lots of products that look expensive but offer little. In this article, we discuss five supplement categories that disappoint more often than they deliver. Not to scare you off, but to help you make smarter choices. Because context matters: sometimes these products are useful.

1. Cheap multivitamins: the illusion of completeness

Most people buy a multivitamin thinking: "everything in one, easy, safe." The problem isn’t the concept, but how it’s carried out.

The quality problem

Many inexpensive multivitamins use the cheapest forms of vitamins and minerals. For magnesium, whether that means a form is absorbed less well is less clear than is often claimed. A review by Schuchardt & Hahn (2017, Current Nutrition and Food Science) concludes that the type of magnesium salt matters less than is often thought and that it is unclear which form is absorbed best. The dose and your own magnesium status matter more¹.

Additionally, some nutrients can interfere with each other when taken at the same time. Calcium and iron, for example, compete for the same absorption pathways in the gut (Hallberg et al., 1991)². A multivitamin forces you to take them together.

A review in Annals of Internal Medicine found no clear long-term benefits of multivitamins for healthy adults (Fortmann et al., 2013)³.

When is a multivitamin useful?

• On a highly restricted diet (vegans may benefit from B12/D3/iodine)
• After bariatric surgery, when absorption is reduced
• As a temporary bridge to address nutritional deficiencies, but targeted supplements are preferable

The alternative: Invest in high-quality individual supplements so you know exactly what you’re taking and in what form. At GOYU you’ll find individual supplements with the ingredients and the amount per daily dose on the label, so you can choose based on your actual needs.

2. Weight gainers: calories without context

Weight gainers (ready-made calorie bombs in powder form) promise muscle growth and weight gain. What they typically deliver: cheap maltodextrin, sugar, and a hefty dose of empty calories.

The problem

The research is clear: muscle growth requires sufficient protein intake (1.6–2.2 g per kg of body weight per day) and a calorie surplus, but the source of those calories matters (Morton et al., 2018, British Journal of Sports Medicine)⁴. Carbohydrates from maltodextrin strongly stimulate insulin and are easily stored as fat, not muscle, when you’re in a calorie surplus.

When ARE weight gainers useful?

• For people with extremely high calorie needs (hardgainers, serious endurance athletes) who struggle to eat enough
• As a temporary addition to a structured bulking program with sufficient protein intake

The alternative: Make your own shake with oats, banana, peanut butter, whole milk (or a plant-based alternative), and a quality protein powder. You control the macronutrient composition, and the nutritional value is considerably higher.

3. Melatonin: useful, but not for daily use

Melatonin has built a reputation as a sleep supplement. In the Netherlands, it is now available over the counter (OTC) in low doses. Being available over the counter does not mean it is the right solution for every sleep complaint.

What melatonin is effective for

Melatonin has mainly been studied for jet lag after flights across multiple time zones. A meta-analysis in the Cochrane Database of Systematic Reviews examined both eastbound and westbound flights (Herxheimer & Petrie, 2002)⁵. It is also sometimes used temporarily by shift workers.

What melatonin is less effective for

Chronic sleep problems usually have a behavioral or physiological cause. Melatonin does not address the cause. With long-term use, the body may become less sensitive to its own melatonin levels, although evidence on this is still limited. Poor sleep hygiene, screen use before bed, irregular bedtimes, or underlying stress cannot be resolved with a supplement.

When IS melatonin useful?

• Temporarily when traveling by plane (0.5–3 mg, 30 minutes before your desired bedtime at your destination)
• As support for a sleep routine when working shifts
• Temporarily when adjusting your sleep schedule

The alternative for structural sleep problems: Improve sleep hygiene and consult your GP if sleep problems persist.

4. BCAAs: paying for three out of nine

BCAAs (branched-chain amino acids: leucine, isoleucine, and valine) are widely promoted in the sports world. However, they are only 3 of the 9 essential amino acids your body needs for protein synthesis.

The problem

Protein synthesis requires all 9 essential amino acids. If one amino acid is missing or present in too low a concentration, synthesis is limited: the so-called "rate-limiting amino acid" principle. A study published in the Journal of the International Society of Sports Nutrition showed that BCAA supplementation without sufficient amounts of the other essential amino acids is suboptimal for muscle growth (Wolfe, 2017)⁶.

Leucine certainly plays a direct role in activating mTOR (the muscle growth signaling pathway), but this effect is greater when all essential amino acids are present, as they are in a complete protein source.

One additional point: leucine stimulates insulin release. For those who train fasted or follow intermittent fasting, this technically breaks the fast.

When are BCAAs useful?

• For vegans who struggle to get enough leucine from plant sources
• As a flavor-neutral alternative to energy drinks during prolonged training

The alternative: A high-quality whey protein (or plant-based alternative with a complete amino acid profile) provides all 9 essential amino acids, including plenty of leucine, for less per serving of protein.

5. Casein and beef protein: the hype vs. reality

Casein

Casein is promoted as a "slow" protein, ideal for nighttime. The idea makes sense: casein is indeed broken down more slowly than whey. But its clinical relevance is limited. Research shows that protein synthesis remains elevated for only 3–5 hours after a protein meal, regardless of absorption rate (Boirie et al., 1997, PNAS)⁷. The benefit of "slow release throughout the night" is marginal for most people.

Casein also contains less leucine per gram of protein than whey, making the anabolic stimulus per serving slightly lower.

Beef protein isolate

This is the most interesting case. Beef protein is promoted as an alternative to dairy protein, but the raw material is generally not protein-rich meat, because that goes to the food industry and meat-processing sector. Beef protein isolates often come from collagen in skin, carcasses, and connective tissue, which has a low leucine content (sometimes <5% vs. >10% for whey). Always check the amino acid profile.

When is casein useful?

• For people who tolerate dairy well and deliberately choose a slower-digesting protein source before bed
• As a supplement to an already adequate daily protein intake

When is beef protein useful?

• For people with lactose intolerance or dairy sensitivity as an alternative to whey
• Provided the amino acid profile is complete: always check the label

The common thread: consider the context

None of these supplements are inherently "bad." The problem is marketing that positions them as universal solutions, when they are only useful in specific contexts, and often at lower doses or less frequently than the packaging suggests.

The basics remain: nutrition, sleep, training, and stress management do more than any supplement. Supplements are an addition, not a replacement.

GOYU alternatives

Disclaimer

This article is intended for informational and consumer education purposes. It is not medical advice and does not replace a consultation with a doctor, dietitian, or nutritionist. Dietary supplements are not medicines and should not be used to prevent or treat diseases. Always consult a healthcare provider if you have concerns about deficiencies or supplement use.

Frequently asked questions (FAQ)

Are supplements even necessary if I eat healthily? For most healthy adults with a varied diet, no. Exceptions are vitamin D (too little sun in the Netherlands), B12 for vegans and iodine for people who don’t eat bread. If in doubt, have your blood levels tested.

How do I know if a supplement is well absorbed? You can’t tell from the packaging. You can read the form of the compound on the label, such as magnesium citrate or magnesium oxide, or vitamin D3 or D2. For magnesium, a review by Schuchardt & Hahn (2017) found that it is unclear which form is absorbed best¹. If the form isn’t listed, you don’t know what you’re buying.

Is melatonin addictive? There is no evidence of physical dependence. However, long-term use can become a psychological habit. Preferably use melatonin for no more than 2–4 consecutive weeks.

When do I actually need BCAAs as an athlete? Almost never if you eat enough protein (1.6–2.2 g/kg/day). The only niche case is training completely fasted when you don't want an extra insulin spike, but even then, the benefits are marginal.

How much protein do I need per day? For inactive adults: 0.8 g/kg. For strength athletes: 1.6–2.2 g/kg. For endurance athletes: 1.2–1.6 g/kg. Spread it across several meals of 20–40 g each for optimal use.

Can I simply stop taking supplements I'm already using? You can usually stop taking most supplements. Exception: if you have been using high doses for a long time or are taking a supplement prescribed by a doctor, always consult your doctor.

Sources

1. Schuchardt JP, Hahn A. (2017). Intestinal Absorption and Factors Influencing Bioavailability of Magnesium-An Update. Current Nutrition and Food Science, 13(4):260–278. PubMed

2. Hallberg L, Brune M, Erlandsson M, Sandberg AS, Rossander-Hultén L. (1991). Calcium: effect of different amounts on nonheme- and heme-iron absorption in humans. American Journal of Clinical Nutrition, 53(1):112–9. PubMed

3. Fortmann SP, Burda BU, Senger CA, et al. (2013). Vitamin and Mineral Supplements in the Primary Prevention of Cardiovascular Disease and Cancer. Annals of Internal Medicine, 159(12):824–834. PubMed

4. Morton RW, Murphy KT, McKellar SR, et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine, 52(6):376–384. PubMed

5. Herxheimer A, Petrie KJ. (2002). Melatonin for the prevention and treatment of jet lag. Cochrane Database of Systematic Reviews, (2):CD001520. PubMed

6. Wolfe RR. (2017). Branched-chain amino acids and muscle protein synthesis in humans. Journal of the International Society of Sports Nutrition, 14:30. PubMed

7. Boirie Y, Dangin M, Gachon P, et al. (1997). Slow and fast dietary proteins differently modulate postprandial protein accretion. Proceedings of the National Academy of Sciences, 94(26):14930–14935. PubMed